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Patent US3351495A successfully refreshed from Google Patents.
US3351495A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Battery separator
Assignee: WR Grace and Co
•
Filing: 1966-11-22
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Granted: 1967-11-07
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Expires: 1986-11-22
Abstract
No abstract record available.
Inventors
- 👤 Larsen Donald Wayne
- 👤 Kehr Clifton Leroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:51
CPC Classifications
H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/414; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S264/00; Y10S264/13
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
38 words
A BATTERY SEPARATOR HAVING AN ESSENTIALLY FLAT SURFACE AND COMPRISING A MICROPOROUS POLYOLEFIN HAVING A MOLECULAR WEIGHT OF AT LEAST 300,000, A STANDARD LOAD MELT INDEX OF SUBSTANTIALLY 0, AND A REDUCED VISCOSITY OF NOT LESS THAN 4.0.
Claim 2
Dependent Claim
38 words
A BATTERY SEPARATOR HAVING AN ESSENTIALLY FLAT SURFACE AND COMPRISING A MICROPOROUS POLYOLEFIN HAVING A MOLECULAR WEIGHT OF AT LEAST 300,000, A STANDARD LOAD MELT INDEX OF SUBSTANTIALLY 0, AND A REDUCED VISCOSITY OF NOT LESS THAN 4.0.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-11-06 | 1971-05-08 | 1971-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-11-06 | 1975-05-08 | 1975-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-11-06 | 1979-05-08 | 1979-11-07 | $7700.00 | Window Closed / Lapsed |